In SolrCloud each of your Core will become a Collection. Each Collection will have its own set of Config Files and data. You might find this helpful Moving multi-core SOLR instance to cloud Solr 5.0 (onwards) has made some changes on how to create a SolrCloud setup with shards, and...

Summary: False sharing and cache-line ping-ponging are related but not the same thing. False sharing can cause cache-line ping-ponging, but it is not the only possible cause since cache-line ping-ponging can also be caused by true sharing. Details: False sharing False sharing occurs when different threads have data that is...

In order to have both MPI processes placed on separate cores of the same socket, you should pass the following options to mpiexec: -genv I_MPI_PIN=1 -genv I_MPI_PIN_DOMAIN=core -genv I_MPI_PIN_ORDER=compact In order to have both MPI processes on cores from different sockets, you should use: -genv I_MPI_PIN=1 -genv I_MPI_PIN_DOMAIN=core -genv I_MPI_PIN_ORDER=scatter...

This is not safe without the lock. Copying the reference to the list doesn't really do anything for you in this context. It's still quite possible for the list that you are currently iterating to be mutated in another thread while you are iterating it, causing all sorts of possible...

This looks like the answer I actually needed. The minimizer may not run multithreaded, but the matrix operations in the function I'm minimizing can. Get GNU Octave to work with a multicore processor. (Multithreading)...

The method Thread.currentThread() returns the thread which we are currently running inside. It is simply a way of saying: "Hey give me a reference of the thread that is running me" Suppose we have four cores and four threads A,B,C and D are running absolutely concurrently, calling this method at...

No, Java 8 does not automatically distribute the work on all CPU cores, unless your code requests it explicitly (for example by using parallel streams). Automatic parallelization is a research area and is not present in mainstream languages. You can use a profiler to find out what is going on...

As I understand, synchronization primitives won't affect cache coherency at all. Cache is French for hidden, it's not supposed to be visible to the user. A cache coherency protocol should work without the programmer's involvement. Synchronization primitives will affect the memory ordering, which is well defined and visible to the...

Whenever there is any sort of context switch the OS will save its state such that it can be restarted again on any core (assuming it has not been tied to a specific core using a processor affinity function). Saving a state that for some reason or other is incomplete...

glcm is not coded to run in parallel, but given that you are processing 488 rasters, I wouldn't worry about running the algorithm itself in parallel - processing the rasters in parallel (say two at a time on an average laptop machine, more if you have more processing pwer and...

MS actually has an in-depth article on the counters underlying Stopwatch. Acquiring high-resolution time stamps A relevant excerpt: In general, the performance counter results are consistent across all processors in multi-core and multi-processor systems, even when measured on different threads or processes. Here are some exceptions to this rule: Pre-Windows...

Your example is perfectly fine. The problem is the minimal workload for the two threads. Section 1 is scheduled to thread #0 and Section 2 to thread #1. However, thread #0 finished his work before the thread #1 has started. It just look like sequential execution of your sections. I...

Why do you need it? Most of its functionality has been integrated into the parallel package which already comes with R. Have a look at its vignette, eg from within R via vignette() or else from here. And the reason you cannot install 'multicore' is because it has been withdrawn...

A. How does a multi-core computer differ from a distributed or a clustered system with respect to the OS? a. Clustered systems are typically constructed by combining multiple computers into a single system to perform a computational task distributed across the cluster. Multiprocessor systems on the other hand could be...

Probably the simplest way for you to confirm that you're running on both cores is to do something like a tight while loop that will spike the processor usage: #include <mpi.h> int main(int argc, char** argv) { MPI_Init(&argc, &argv); while(1) {} } Then you can to look at your usage...

The foreach ".errorhandling" argument is intended to help in this situation. If you want foreach to pass errors through, then use .errorhandling="pass". If you want it to filter out errors (which reduces the length of the result), then use .errorhandling="remove". The default value is "stop" which throws an error indicating...

It seems you are loading and storing exclusively with mm_load_ps and mm_store_ps, which load and store 4 floats in a single instruction. Since your containers (matrixes and vectors) do not have necessarily a size which is a multiple of 4 floats (16 bytes) this is incorrect. memalign ensures that the...

Your code contains a race condition. The conflicting statements are the assignment a[i+1] = b[i]; that writes to the array a and the statement totalA += a[i]; that reads from a. In your code there is no guarantee that the iteration that is responsible for writing to a particular location...

In node v0.10, the OS kernel always chooses which child gets the request. In node v0.11+ and io.js v1.0.0+, manual round-robin scheduling is used (except on Windows for now). This default behavior is configurable by setting an environment variable though.